不同烧结烟气脱硫工艺应用比较与分析

COMPARISON AND ANALYSIS OF DIFFERENT DESULFURIZATION TECHNOLOGIES APPLIED IN SINTERING FLUE GAS

研究分析了烧结烟气中SO_2的形成机理、各段SO_2浓度变化规律,分析了国内几种典型脱硫技术的脱硫原理、工艺流程、技术特点及存在的问题。根据不同钢铁企业在线监测得到实际的脱硫数据,总结了各种工艺的减排效果、工况适应性、技术稳定性、经济性、副产物利用、设备维护及废水处理情况等。研究分析得出:氧化镁法脱硫效率最高,平均在93%~93.5%;石灰石-石膏法脱硫效率平均值达92.8%,技术最稳定成熟,应用最广泛,约占比60%;钢渣脱硫技术不成熟,脱硫效率不稳定,最小值为79.9%,平均值为92.6%,相差较大。半干法工艺脱硫效率相对较低,其中密相干塔法脱硫效率平均为78.3%,适用于SO_2浓度较低的烟气。

The forming mechanism of SO_2in the sintering flue gas and changing rule of SO_2concentration in different segments were investigated.The several typical domestic flue gas desulfurization technologies were analyzed,including desulfurization principle,technological processes,technical features and the existing problems.The emission reduction effect,working conditions adaptability,technology stability,economical efficiency,by-products utilization,equipment maintenance and wastewater treatment were summarized,based on the on-line monitoring data of desulfurization in different iron and steel enterprises.It could be obtained that desulfurization efficiency was the highest by magnesium oxide method and the average value reached 93%~93.5%.Limestone-gypsum method was the most mature,stable,widely-used so that it accounted for about 60%in all desulfurization technologies.The high average value of desulfurization efficiency was 92.8%.However,the steel slag desulfurization technology was immature and desulfurization efficiency was unstable,with a minimum value of79.9%,and an average value of 92.6%.The desulfurization efficiency was relatively low in semidry method.The dense coherent tower method was suitable for low SO_2concentration in flue gas and its average desulfurization efficiency was 78.3%.